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A motor boat whose speed is 20 km/h in still water takes 2 hour more to go 34 km upstream than to return downstream to the same spot. Find the speed of the stream. Notes:-❌❌Unwanted answer will be reported ❌❌❗️❗️Donot copy paste from google❗️❗️✔️✔️Answer the question in your rough copy✔️✔️✔️✔️Best answer will be mark as brainliest✔️✔️ |
| Answer» SPEED of boat =18km/hrDistance =24kmLet X be the speed of stream.Let t 1 and t 2 be the time for upstream and DOWNSTREAM.As we know that,speed= TIMEDISTANCE ⇒time= speeddistance For upstream,Speed =(18−x)km/hrDistance =24kmTime =t 1 Therefore,t 1 = 18−x24 For downstream,Speed =(18+x)km/hrDistance =24kmTime =t 2 Therefore,t 2 = 18+x24 Now according to the question-t 1 =t 2 +118−x24 = 18+x24 +1⇒ 18−x1 − 18+x1 = 241 ⇒ (18−x)(18+x)(18+x)−(18−x) = 241 ⇒48x=(18−x)(18+x)⇒48x=324+18x−18x−x 2 ⇒x 2 +48x−324=0⇒x 2 +54x−6x−324=0⇒x(x+54)−6(x+54)=0⇒(x+54)(x−6)=0⇒x=−54 or x=6Since speed cannot be negative.⇒x=−54∴x=6Thus the speed of stream is 6km/hrHence the correct answer is 6km/hr.Answered By442 ViewsHow satisfied are you with the answer?This will help us to improve betteranswrGet Instant Solutions, 24x7No Signup requiredgirlstarRelated Questions to studyTwo equal sides of a triangle are each 4m less than three times the third side. Find the dimension of the triangle, if its perimeter is 55m.Study laterView AnswerFind the maximum distance of the point (k,0) from the curve 2x 2 +y 2 −2x=0 | |